The term "arrested", which only applies once a person has been charged with a crime, may soon include those detained without charge, under proposals in the Criminal Justice Bill.
But police representatives and MSPs fear removing the decades-old distinction between detention and arrest could confuse police officers, leading to bad paperwork and more cases being thrown out of court.
The general public may also believe that someone held under the new term of "arrested on the ground of reasonable suspicion" is more likely to be guilty as arrest was previously an escalation of detention, Holyrood's Justice Committee heard.
The Scottish Government believes the change will make the process of detention and arrest simpler and clearer, but the committee heard fears that it could have the opposite effect.
Calum Steele, general secretary of rank-and-file body the Scottish Police Federation, said: "Police officers know the process of detention, and the unlearning of that and the learning of something else is going to result in the inadvertent misapplication of the wrong pieces of legislation and information.
"I just fear that the consequence of just changing terminology without largely changing its content, and having perhaps the wrong information recorded as a consequence of dealing with a new set of processes, albeit applying the general principles of fairness, could lead to cases being thrown out of court."
Lessons should be learned from the murder in England of architect Jo Yates, where her landlord was arrested and smeared by the media but subsequently released, he said.
"The landlord, Christopher Jefferies, who happened to be quite an eccentric-looking gentleman, was arrested. I can't speak for what the general public across the whole of the UK thought, but my sense from the subsequent furore surrounding it was that they thought this man was guilty because the terminology applied was 'arrested'," Mr Steele said.
"I don't sense that when someone is detained in Scotland and then subsequently arrested that there is a difficulty in understanding the difference between the two."
Chief Superintendent David O'Connor, president of the Association of Scottish Police Superintendents, said: "Whilst it appears on the surface to be a relatively simple change, I think there will be significant training issues for the police service to make sure the people fully understand what the change means, and understand the moving from detention to arrested on suspicion."
Committee convener Christine Grahame, an SNP MSP, said: "I remain unconvinced at the moment that changing the terminology is helpful. The perception, whether employers know anything about it or the perception amongst other employees, is if you are arrested on suspicion, it's very hard to shake that mud off.
"In the Yates case, the man was convicted, hung, drawn and quartered (in the media) because he looked odd and he was arrested.
"The concern is about innocent people perhaps being found guilty by the tabloid press and by broadsheets."
The SNP administration at Holyrood has said it is "persuaded of the logic of having a single state of custody, which simplifies and clarifies rights and procedures for police and arrested persons alike".
A policy memorandum accompanying the Bill states: "The Carloway review (of criminal law and practice) concluded that the distinction between arrest and detention had been eroded to such an extent that there was little purpose in continuing with the two different states.
"Lord Carloway recommended that it would be simpler, and more clearly in tune with the European Convention on Human Rights, to have a single period of custody (detention), once a person has been arrested on suspicion of having committed an offence."
The Law Society of Scotland believes the system of arrest and detention does not need changed.
Grazia Robertson, from the society's criminal law committee, said: "The Bill aims to modernise and simplify procedure but what is being proposed seems more complex, more bureaucratic and potentially more costly than it is at the moment.
"We don't believe there is a need to introduce separate stages for when an arrested person is 'not officially accused' and 'officially accused' when the current system of arrest and detention is already compliant with ECHR (European Convention on Human Rights) and is widely understood and working well."
In its written response to the Bill, the society raised concerns about new police powers which would allow conditions to be imposed on people released from custody but who have not been charged with any offence.
Ms Robertson said: "We have to remember that these will be people who have not been charged with having committed any crime but are nevertheless obliged to conform to certain conditions after being released, which could mean staying away from their place of work or home for almost a month while police continue to carry out investigations. This is a different situation from someone who has been charged but has been granted bail by the courts until their next court appearance.
"We're also concerned that the Bill as drafted sets a blanket 28 days for the period of investigative liberation rather than it being up to 28 days, as recommended by Lord Carloway in his report."