COLUMBIA — Lawmakers who include pet projects in bills unrelated to the main topic — sometimes called "bobtailing" — are violating the state constitution, South Carolina's top court said Monday.

It is not clear if the ruling will automatically force legislators to reform their ways, but the decision is another victory for watchdog activist Edward Sloan Jr., who has taken on a variety of public entities for failing to follow what he contends are legal procedures.

In the seven-page opinion, the state Supreme Court sided with Sloan in a suit against House Speaker Bobby Harrell, Lt. Gov. Andre Bauer and the state of South Carolina, ruling that individual add-ons, such as those covering wine-tastings or renewable energy development, should be stricken from a bill titled "Job Tax Credit."

The state constitution provides that "every Act or resolution having the force of law shall relate to but one subject, and that shall be expressed in the title," the court wrote.

That keeps legislators and the public informed about a bill's intent and prevents "legislative logrolling."

Sloan's attorney had argued that lawmakers abuse their power when they slide unrelated legislation into other measures.

On Monday, attorney Jim Carpenter said he was pleased the justices sided with his client but was disappointed they appeared to pick and choose which provisions to strike from the laws.

"We think it's time that the court strike acts in their entirety so that, No. 1, the constitution is upheld, and No. 2, I would think the General Assembly would be more careful," Carpenter said.

Carpenter said the court addressed only four of Sloan's challenges to statewide bills from 2007 but declined to rule on five pieces of so-called "local" single-county legislation that Sloan also challenged.

One of those acts was sponsored by two Charleston lawmakers and added two members to the Charleston Aviation Authority, both of whom were lawmakers.

The court ultimately ruled that Sloan didn't have the standing to challenge those measures, which were also considered unconstitutional by the governor and the state attorney general, Carpenter said. It's a step backward, Carpenter said.

Sloan and Carpenter sued over a similar case in 2004 against state lawmakers, arguing that legislation that began as a research and development bill ballooned to include 15 other subjects tacked on by legislators.

The justices eventually sided with Sloan, throwing out parts of the bill, including a culinary arts program at Trident Technical College in Charleston, but kept the original legislation intact.

All four of the bills mentioned in Carpenter's more recent brief survived after lawmakers overrode vetoes by Gov. Mark Sanford. A spokesman for Sanford said Monday he was glad Sloan had pursued the case but agreed with Carpenter that throwing out whole bills would have more of an impact on legislators.

Harrell did not return a phone message seeking comment.