ATTLEBORO --Fall River attorney Sam Sutter formally announced his candidacy for the Democratic nomination for Bristol County district attorney Wednesday, and challenged incumbent Paul Walsh Jr. to four debates starting in Attleboro.

Walsh declined the challenge to debate Sutter.

`` He'll just focus on his own campaign,'' Walsh spokesman Ryan Phelan said.

Sutter, a former Bristol County assistant district attorney, launched his campaign with stops in New Bedford, Fall River, Taunton and Attleboro.

Sutter told about 40 supporters outside Attleboro District Court that he wants to debate Walsh in Attleboro in June, Taunton in July, Fall River in August and New Bedford in September. The Democratic primary is Sept. 19.

There is no announced Republican candidate for the post.

Sutter attacked Walsh's 16-year record on numerous points, including sentencing on the most serious of drug cases.

Sutter said legislation passed in the late 1980s established a minimum 10-year prison sentence for trafficking more than 100 grams of cocaine and 15 years for more than 200 grams.

`` Paul Walsh routinely reduces those crimes. That will never happen under a Sam Sutter administration,'' Sutter said.

Sutter promised to try to prevent crime by identifying potential threats with information from police, school officials and residents.

`` If we do, we can identify those individuals before they go into bars and kill people,'' Sutter said.

He was referring to Jacob D. Robida of New Bedford, who went on a rampage last month in a popular gay nightclub in New Bedford.

Sutter pledged to reduce the flow of guns into Bristol County by getting superior court orders for wiretaps on suspects.

`` For some reason, Paul Walsh abandoned that very effective'' method, Sutter said. Sutter worked for Walsh for eight years, including 18 months as an assistant district attorney during the mid-1990s.

Walsh called Sutter `` a loyal employee, as well as a good friend.''

`` I look forward to a vigorous campaign,'' Walsh said in a statement issued Wednesday.

Sutter said he is running because `` change is needed in the leadership of that important office.''

`` We've had 16 years of the same approach, the same style, the same methods of fighting crime. It's not working well enough,'' Sutter said.

rdrtrdrsrdrw15rsp160 MICHAEL GELBWASSER can be reached at 508-236-0372 or at mgelbwasser(at)(at)thesunchronicle.com.