A deputy chief from a Massachusetts told legislative task force Wednesday that the changes it made to criminal line ups are feasible even for very small police departments.

Wellesley Deputy Chief William G. Brooks spoke before a state task force charged with studying whether changes to the way criminal lineups are presented to witnesses can reduce the risk of identifying the wrong person.

Studies have found that when witnesses are shown potential suspects one-by-one rather than all at once, they are less likely to identify the person who looks most like the offender rather than the actual offender.

Other reforms have also been effective like ensuring the officer presenting the lineup or photo array cannot tell if the witness is looking at the individual the police suspect is the offender. This “blind” method prevents the officer from inadvertently suggesting to the witness which individual is guilty.

However, some police officials have expressed fears that it would be difficult for small police departments with limited resources to conduct sequential and blind lineups. In departments with a small number of officers, it could be hard to find an officer who doesn’t already know who the suspect is.

Brooks said his department, with around 40 sworn officers, has not had a problem since they enacted the reforms in 2005. He suggested there are methods by which even the smallest department can conduct reliable lineups.

“I really do think that regardless of your size, there’s a way to show an array to ensure that you don’t influence the selection,” he said.

One method he suggested was to take photos of potential subjects, place them in individual envelopes, shuffle the envelopes and allow the witness to look at them one by one. That way the officer does not know which photo the witness is viewing and the witness cannot compare photos to pick the one that looks most like the suspect.

Brooks said investigators could also try making a PowerPoint presentation with a single photo on each slide and leave the room while witnesses clicked through the slides.

“I mean really, pretty simple stuff. If you were the only policeman in your department you could show photo arrays blind if you wanted to,” he said.

Brooks admitted he recoiled when the reforms were first suggested to him, especially the suggestion that the lead investigator should not be in the room as witness look at lineups or photo arrays.

“The idea that the primary would take his case and turn it over to somebody who didn’t know anything about the case and send them off to see the witness when the detective typically worked so hard at establishing a rapport, I just thought was a terrible idea,” he said.

Brooks said he warmed up to the idea after some training. He said he now conducts training on the topic and has found it is vitally important. It is difficult to tell a detective to just toss out investigative techniques he or she has been using for 20 years, he said. But when detectives have a good understanding of the process and purpose of the changes they are generally receptive, he said.

While Connecticut does not mandate that police officers use sequential lineups, the legislature did pass a law last session requiring the lineups be conducted blind, whenever it is practical, as of the beginning of next year.

Looking at the statute, Brooks recommended changes to the language. The law says that “the person conducting the identification procedure shall be a person who is not aware of which person in the photo lineup or live lineup is suspected as the perpetrator of the offense.”

Brooks said the language is too broad and may prevent small departments from using the folder method he had previously discussed. Instead the statute should be worded in a way that allows for the person conducting the interview to know who the suspect is so long as he does not know which photograph the witness is looking at, he said.

The task force was created by legislation, which as originally drafted, would have mandated Connecticut police departments use one-at-a-time sequential lineups. The bill was changed to create the group, which will make recommendations to the General Assembly for the next session after studying the issue.